Cemented filling stope engineering parameter design method and system

Abstract

The invention discloses a cemented filling stope engineering parameter design method and system, and the design method comprises the following steps: building a filling material theoretical carbon dioxide sequestration potential and mineralization mechanical property database through a cemented filling material CO2 mineralization multi-factor coupling laboratory test; analyzing mine mining geological conditions and filling requirements according to the database, and inverting the maximum allowable deformation of the protected object through a numerical simulation model; determining the critical support stiffness of the stope support system by combining the maximum allowable deformation with the elastic foundation equivalent stiffness principle; taking a filling roadway arrangement mode and a material ratio as decision variables, establishing a collaborative optimization model taking the total carbon sequestration amount and the comprehensive economic cost as optimization targets, and solving a Pareto optimal engineering parameter set through an optimization algorithm; and applying the optimal parameters to the field, and adjusting a filling roadway arrangement mode and material proportioning parameters according to field practice feedback to obtain an optimal solution under requirements.

Description

TECHNICAL FIELD

[0001] The present application relates to the cross-disciplinary field of mining, environmental protection and chemical engineering, and particularly relates to a method and system for designing engineering parameters of a cemented filling stope considering carbon dioxide mineralization. BACKGROUND

[0002] The coal industry is facing severe low-carbon transformation pressure, and the ground accumulation of coal gangue and other solid wastes has caused serious land occupation and environmental pollution. Using alkaline solid wastes such as coal gangue and fly ash to construct underground filling bodies and perform CO2 mineralization sequestration is an effective way to organically combine solid waste large-scale disposal, goaf rock control and carbon permanent sequestration, and has important engineering value and social significance for building green and low-carbon mines.

[0003] The existing cemented filling stope engineering parameter design still uses the traditional engineering design method, and lacks scientific consideration of the carbon dioxide mineralization effect. Although the mineralization reaction realizes carbon sequestration, it changes the strength of the cemented filling body: carbon dioxide consumes active calcium in the system and forms an inclusion layer to hinder hydration, resulting in a significant decline in the macroscopic strength of the filling body. The traditional design concept often ignores this characteristic, and the weakened support stiffness cannot meet the key layer control requirements, which is prone to cause aquifer instability or excessive surface subsidence; if the cement dosage is simply increased to resist mineralization damage, the economic cost will increase dramatically, and the traditional method cannot quantify the potential benefits of carbon sequestration, and cannot maximize engineering benefits.

[0004] Therefore, it is urgent to develop a collaborative design method that takes into account the "mineralization strength reduction", "filling space layout" and "carbon sequestration comprehensive benefits". By scientifically adjusting the filling roadway layout pattern to compensate for the loss of material strength, the best balance point of stope stability, economic cost and carbon sequestration benefits is sought under the framework of multi-objective optimization, and the carbon sequestration in the cemented filling technology is promoted to the engineering application. SUMMARY

[0005] The present application proposes a cemented filling stope engineering parameter design method and system to address the problems and needs mentioned above. The technical features adopted can achieve the above technical purposes and bring other technical effects.

[0006] One object of the present application is to propose a cemented filling stope engineering parameter design method, comprising the following steps: S10: Establish a database of theoretical carbon dioxide sequestration potential and mineralization mechanical properties of filling materials through CO2 mineralization multi-factor coupling laboratory tests of cemented filling materials; S20: Based on the above database analysis of the mining geological conditions and backfilling requirements of the mine, and based on the properties of the surrounding rock and the backfilling technology of the stope, the maximum allowable deformation of the protected object is inverted through a numerical simulation model; the critical support stiffness of the stope support system is determined by combining the maximum allowable deformation with the principle of equivalent stiffness of elastic foundation. S30: Using the layout pattern and material ratio of the filling tunnel as decision variables, and under the premise of ensuring the safety of the protected object, a collaborative optimization model is established with the total carbon sequestration and comprehensive economic cost as optimization objectives, and the Pareto optimal engineering parameter set is solved by optimization algorithm; S40: Apply the optimal parameters to the field, and adjust the layout mode of the filling tunnel and the material ratio parameters according to the feedback from field practice to obtain the optimal solution under the requirements.

[0007] Furthermore, the cemented backfilling stope engineering parameter design method according to the present invention may also have the following technical features: In one example of the invention, in step S10, the theoretical carbon dioxide sequestration potential of the filling material is determined. The calculation is performed using the modified Steinour formula, which is expressed as follows: In the formula, , , , and Each chemical formula represents the mass percentage of the corresponding oxide in the material; β is the engineering correction factor.

[0008] In one example of the present invention, in step S20, based on the properties of the surrounding rock and the backfilling process of the mining area, the maximum allowable deformation of the protected object is determined by numerical simulation model, specifically including the following steps: S21: Based on the database of mineralization mechanical property evolution, establish a constitutive equation that reflects the evolution of the strength of the filling body with the degree of mineralization, and map the mechanical parameters under different mineralization degrees to the model unit; S22: Based on the mining geological conditions and typical backfill roadway layout patterns, establish a corresponding spatial distribution model of backfill bodies and roadway retention. S23: Simulate the movement characteristics of the surrounding rock in the mining area under the combined effect of the strength evolution of the backfill and the spatial layout through numerical simulation model, obtain the full-cycle settlement data of the protected object, and use this to invert and calculate the allowable displacement control threshold required to maintain the protected object.

[0009] In one example of the present invention, step S20 further includes: based on the principle of equivalent stiffness of elastic foundation, and according to the deformation control requirements of the protected object, constructing a criterion for the critical deformation resistance capacity required by the mining support system, which satisfies the following relationship: In the formula, The critical equivalent deformation resistance parameter required for the mining support system under exposed goaf conditions; The equivalent load strength parameter of the rock mass above the goaf acting vertically on the mining area; This refers to the parameter representing the extent of the influence of the goaf in the horizontal direction. The allowable displacement control threshold is determined based on the safety status of the protected object.

[0010] In one example of the present invention, in step S30, a collaborative optimization model is established with the total carbon sequestration and comprehensive economic cost as optimization objectives, specifically including the following steps: S31: Design variable X n The layout pattern of the filling roadway, the cementitious agent ratio, and the CO2 content are selected as decision variables; wherein, the layout pattern of the filling roadway is quantitatively characterized by the filling layout coefficient λ. S32: Constructing the objective function F(X): including: constructing the function to maximize total carbon sequestration J C and minimizing the overall cost J E ; Among them, maximizing the total carbon sequestration J C The expression is: In the formula, Let λ be the total volume of the goaf in the mining area, and λ be the filling layout coefficient. Carbon sequestration per unit volume of filling material; Among them, minimizing the comprehensive cost J E The expression is: In the formula, For material costs, For process costs; S33: Construct the constraint function G(X); its expression is: In the formula, These are the critical deformation resistance parameters for the mining support system. In design variable X n The equivalent deformation resistance function of the mining support system under certain conditions.

[0011] In one example of the present invention, in step S32, the carbon fixation amount per unit volume of filling material is... The expression is: In the formula, Theoretical carbon dioxide sequestration potential, Mineralization The wet density of the filling material; This represents the water content of the filling material.

[0012] In one example of the present invention, in step S32, the equivalent deformation resistance function of the mining support system is... The expression is: In the formula, An equivalent correction coefficient reflecting the stress state and structural synergy effect of the mining support system. The elastic modulus of the infill material whose strength has decreased after carbon dioxide mineralization. The characteristic height parameter is used to characterize the spatial scale of the mining area.

[0013] In one example of the present invention, in step S40, based on feedback from field practice, the layout pattern of the filling tunnel and the material ratio parameters are adjusted to obtain the optimal solution under the requirements. The specific steps are as follows: S41: Solution stage: The mathematical model is optimized using a multi-objective optimization algorithm, and the Pareto front solution set that satisfies the constraints is output. S42: Feedback and Correction Stage: Select the target solution in the Pareto front for engineering application and monitor the actual deformation evolution data of the mining area; calculate the deviation rate between the measured data and the theoretical prediction, construct the error feedback correction equation, and use the model to adjust the equivalent correction coefficients within the constraint function in step S30. Perform inversion calibration, and use the calibrated parameters to perform a new round of optimization solutions until the target requirements of the protected object are met.

[0014] Another object of the present invention is to provide a design system for engineering parameters of cemented backfilling stopes, comprising: The database module is configured to establish a database of the theoretical carbon dioxide sequestration potential and mineralization mechanical properties of cemented backfill materials through multi-factor coupled laboratory testing of CO2 mineralization of cemented backfill materials. The inversion and support stiffness module is configured to analyze the mining geological conditions and backfilling requirements of the mine based on the above database, and based on the properties of the surrounding rock and the backfilling process of the stope, invert the maximum allowable deformation of the protected object through the model; and determine the critical support stiffness of the stope support system by combining the principle of equivalent stiffness of elastic foundation. The collaborative optimization module is configured to use the layout mode and material ratio of the filling tunnel as decision variables, and to establish a collaborative optimization model with the total carbon sequestration and comprehensive economic cost as optimization objectives under the premise of ensuring the safety of the protected object. The Pareto optimal engineering parameter set is then solved through the optimization algorithm. The feedback and adjustment module is configured to apply the optimal parameters to the field and adjust the filling tunnel layout and material ratio parameters based on field feedback to obtain the optimal solution under the requirements.

[0015] In one example of the present invention, the inversion and support stiffness module includes: The constitutive model unit is configured to establish a constitutive equation reflecting the evolution of the strength of the filling body with the degree of mineralization based on the database of mineralization mechanical property evolution, and to map the mechanical parameters under different mineralization degrees to the model unit; The spatial distribution model unit is configured to establish a corresponding spatial distribution model of the filling body and the roadway based on the mining geological conditions and typical filling roadway layout patterns of the mine. The displacement inversion calculation unit is configured to simulate the movement characteristics of the surrounding rock in the mining area under the combined effect of the strength evolution of the backfill and the spatial layout through a numerical simulation model, obtain the full-cycle settlement data of the protected object, and invert and calculate the allowable displacement control threshold required to maintain the protected object.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. Breaking through the bottleneck of traditional cemented backfilling methods, an active compensation mechanism that trades space for strength is proposed. By actively optimizing the backfilling layout, the strength reduction caused by mineralization damage of the backfilling material is compensated, effectively ensuring the safety of the protected object.

[0017] 2. By constructing a multi-objective collaborative optimization model, Pareto optimality of carbon sequestration benefits and economic costs was achieved while ensuring the effectiveness of rock strata control, which can take into account multiple aspects such as safety, greenness and economy.

[0018] 3. Maximize the carbon sequestration benefits of goaf areas, promote the green and low-carbon transformation and development of coal mines, and no longer regard backfill as a means of rock strata control, but attach importance to its carbon sequestration capacity value.

[0019] 4. A dynamic correction closed-loop system was constructed, which improved the accuracy and robustness of the design, making the patent universally applicable when facing complex geological conditions on site.

[0020] The preferred embodiments of the invention will be described in more detail below with reference to the accompanying drawings, so as to facilitate an understanding of the features and advantages of the invention. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings of the embodiments of the present invention will be briefly described below. The drawings are merely illustrative of some embodiments of the present invention and are not intended to limit the scope of the present invention to all embodiments.

[0022] Figure 1This is a schematic diagram of the overall process of the cemented backfilling stope engineering parameter design method according to an embodiment of the present invention; Figure 2 The Pareto front solution set distribution and decision logic diagram regarding the filling mode of the multi-objective optimization algorithm according to an embodiment of the present invention are shown below. Figure 3 This is a comparison of aquifer settlement prediction curves under different filling processes according to embodiments of the present invention. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. The same reference numerals in the drawings represent the same components. It should be noted that the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0024] Unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meaning understood by one of ordinary skill in the art to which this invention pertains. The terms “first,” “second,” and similar terms used in this patent application specification and claims do not indicate any order, quantity, or importance, but are merely used to distinguish different components. Similarly, “an” or “a” and similar terms do not necessarily indicate a quantity limitation. Terms such as “comprising” or “including” mean that the element or object preceding the word encompasses the element or object listed following the word and its equivalents, without excluding other elements or objects. Terms such as “connected” or “linked” are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. Terms such as “upper,” “lower,” “left,” and “right” are used only to indicate relative positional relationships; these relative positional relationships may change accordingly when the absolute position of the described object changes.

[0025] According to a first aspect of the present invention, a method for designing engineering parameters for cemented backfilling stopes is provided, such as... Figure 1 As shown, it includes the following steps: S10: Establish a database of theoretical carbon dioxide sequestration potential and mineralization mechanical properties of cemented backfill materials through multi-factor coupled laboratory testing of CO2 mineralization of cemented backfill materials; S20: Based on the above database analysis of the mining geological conditions and backfilling requirements of the mine, and based on the properties of the surrounding rock and the backfilling technology of the stope, the maximum allowable deformation of the protected object is inverted through a numerical simulation model; the critical support stiffness of the stope support system is determined by combining the maximum allowable deformation with the principle of equivalent stiffness of elastic foundation. S30: Using the layout pattern and material ratio of the filling tunnel as decision variables, and under the premise of ensuring the safety of the protected object, a collaborative optimization model is established with the total carbon sequestration and comprehensive economic cost as optimization objectives, and the Pareto optimal engineering parameter set is solved by optimization algorithm; S40: Apply the optimal parameters to the field, and adjust the layout mode of the filling tunnel and the material ratio parameters according to the feedback from field practice to obtain the optimal solution under the requirements.

[0026] This design method breaks through the bottleneck of traditional cemented backfilling methods, proposing an active compensation mechanism that trades space for strength. By actively optimizing the backfilling layout, it compensates for the strength reduction caused by mineralization damage to the backfilling material, effectively ensuring the safety of the protected object. This design method achieves Pareto optimality between carbon sequestration benefits and economic costs while ensuring strata control through the construction of a multi-objective collaborative optimization model, comprehensively considering safety, environmental friendliness, and economy. This design method maximizes the carbon sequestration benefits of goaf areas, promoting the green and low-carbon transformation and development of coal mines, moving beyond simply viewing backfilling as a strata control means to emphasizing its carbon sequestration capacity. This design method constructs a dynamic correction closed-loop system, improving the accuracy and robustness of the design, making the patent universally applicable to complex geological conditions. This design method compensates for the loss of material strength by scientifically adjusting the layout of backfilling roadways, seeking the optimal balance between stope stability, economic costs, and carbon sequestration benefits within a multi-objective optimization framework, promoting the engineering application of carbon dioxide sequestration in cemented backfilling technology.

[0027] In one example of the invention, in step S10, the theoretical carbon dioxide sequestration potential of the filling material is determined. The calculation is performed using the modified Steinour formula, which is expressed as follows: In the formula, , , , and Each chemical formula represents the mass percentage of the corresponding oxide in the material; β is the engineering correction factor.

[0028] In one example of the present invention, in step S20, based on the properties of the surrounding rock and the backfilling process of the mining area, the maximum allowable deformation of the protected object is determined by numerical simulation model, specifically including the following steps: S21: Based on the database of mineralization mechanical property evolution, establish a constitutive equation that reflects the evolution of the strength of the filling body with the degree of mineralization, and map the mechanical parameters under different mineralization degrees to the model unit; S22: Based on the mining geological conditions and typical backfill roadway layout patterns, establish a corresponding spatial distribution model of backfill bodies and roadway retention. S23: Simulate the movement characteristics of the surrounding rock in the mining area under the combined effect of the strength evolution of the backfill and the spatial layout through numerical simulation model, obtain the full-cycle settlement data of the protected object, and use this to invert and calculate the allowable displacement control threshold required to maintain the protected object.

[0029] In one example of the present invention, step S20 further includes: based on the principle of equivalent stiffness of elastic foundation, and according to the deformation control requirements of the protected object, constructing a criterion for the critical deformation resistance capacity required by the mining support system, which satisfies the following relationship: In the formula, The critical equivalent deformation resistance parameter required for the mining support system under exposed goaf conditions; The equivalent load strength parameter of the rock mass above the goaf acting vertically on the mining area; This refers to the parameter representing the extent of the influence of the goaf in the horizontal direction. The allowable displacement control threshold is determined based on the safety status of the protected object.

[0030] In one example of the present invention, in step S30, a collaborative optimization model is established with the total carbon sequestration and comprehensive economic cost as optimization objectives, specifically including the following steps: S31: Design variable X n The layout pattern of the backfill roadway, the cementitious agent ratio, and the CO2 content are selected as decision variables. The layout pattern of the backfill roadway is quantitatively characterized by the backfill layout coefficient λ, which represents the proportion of the volume occupied by the backfill in the goaf and reflects the spatial support structure characteristics under the "inter-roadway backfilling" or "partial backfilling" process. When full roadway backfilling is adopted, λ=1, and when intermittent strip backfilling is adopted, λ is a value less than 1. S32: Constructing the objective function F(X): including: constructing the function to maximize total carbon sequestration J C and minimizing the overall cost J E ; Among them, maximizing the total carbon sequestration J C The expression is: In the formula, Let λ be the total volume of the goaf in the mining area, and λ be the filling layout coefficient. Carbon sequestration per unit volume of filling material; Among them, minimizing the comprehensive cost J E The expression is: In the formula, For material costs, For process costs; S33: Construct the constraint function G(X); its expression is: In the formula, These are the critical deformation resistance parameters for the mining support system. In design variable X n The equivalent deformation resistance function of the mining support system under certain conditions.

[0031] In one example of the present invention, in step S32, the carbon fixation amount per unit volume of filling material is... The expression is: In the formula, Theoretical carbon dioxide sequestration potential, Mineralization The wet density of the filling material; This represents the water content of the filling material.

[0032] In one example of the present invention, in step S32, the equivalent deformation resistance function of the mining support system is... The expression is: In the formula, An equivalent correction coefficient reflecting the stress state and structural synergy effect of the mining support system. The elastic modulus of the infill material whose strength has decreased after carbon dioxide mineralization. The characteristic height parameter is used to characterize the spatial scale of the mining area.

[0033] In one example of the present invention, in step S40, based on feedback from field practice, the layout pattern of the filling tunnel and the material ratio parameters are adjusted to obtain the optimal solution under the requirements. The specific steps are as follows: S41: Solution stage: The mathematical model is optimized using a multi-objective optimization algorithm, and the Pareto front solution set that satisfies the constraints is output. S42: Feedback and Correction Stage: Select the target solution in the Pareto front for engineering application and monitor the actual deformation evolution data of the mining area; calculate the deviation rate between the measured data and the theoretical prediction, construct the error feedback correction equation, and use the model to adjust the equivalent correction coefficients within the constraint function in step S30. Perform inversion calibration, and use the calibrated parameters to perform a new round of optimization solutions until the target requirements of the protected object are met.

[0034] According to a second aspect of the present invention, a system for designing engineering parameters for cemented backfilling stopes includes: The database module is configured to establish a database of the theoretical carbon dioxide sequestration potential and mineralization mechanical properties of cemented backfill materials through multi-factor coupled laboratory testing of CO2 mineralization of cemented backfill materials. The inversion and support stiffness module is configured to analyze the mining geological conditions and backfilling requirements of the mine based on the above database, and based on the properties of the surrounding rock and the backfilling process of the stope, invert the maximum allowable deformation of the protected object through the model; and determine the critical support stiffness of the stope support system by combining the principle of equivalent stiffness of elastic foundation. The collaborative optimization module is configured to use the layout mode and material ratio of the filling tunnel as decision variables, and to establish a collaborative optimization model with the total carbon sequestration and comprehensive economic cost as optimization objectives under the premise of ensuring the safety of the protected object. The Pareto optimal engineering parameter set is then solved through the optimization algorithm. The feedback and adjustment module is configured to apply the optimal parameters to the field and adjust the filling tunnel layout and material ratio parameters based on field feedback to obtain the optimal solution under the requirements.

[0035] This design system breaks through the bottlenecks of traditional cemented backfilling methods, proposing an active compensation mechanism that trades space for strength. By actively optimizing the backfilling layout, it compensates for the strength reduction caused by mineralization damage to the backfilling material, effectively ensuring the safety of the protected object. Through the construction of a multi-objective collaborative optimization model, this system achieves Pareto optimality between carbon sequestration benefits and economic costs while ensuring effective rock strata control, comprehensively considering safety, environmental friendliness, and economy. This system maximizes the carbon sequestration benefits of goaf areas, promoting the green and low-carbon transformation of coal mines, moving beyond simply viewing backfilling as a rock strata control method to emphasizing its carbon sequestration capacity. The system constructs a dynamic correction closed-loop system, improving the accuracy and robustness of the design, making the patent universally applicable to complex geological conditions. By scientifically adjusting the layout of backfilling roadways to compensate for material strength loss, this system seeks the optimal balance between stope stability, economic costs, and carbon sequestration benefits within a multi-objective optimization framework, promoting the engineering application of carbon dioxide sequestration in cemented backfilling technology.

[0036] In one example of the present invention, the inversion and support stiffness module includes: The constitutive model unit is configured to establish a constitutive equation reflecting the evolution of the strength of the filling body with the degree of mineralization based on the database of mineralization mechanical property evolution, and to map the mechanical parameters under different mineralization degrees to the model unit; The spatial distribution model unit is configured to establish a corresponding spatial distribution model of the filling body and the roadway based on the mining geological conditions and typical filling roadway layout patterns of the mine. The displacement inversion calculation unit is configured to simulate the movement characteristics of the surrounding rock in the mining area under the combined effect of the strength evolution of the backfill and the spatial layout through a numerical simulation model, obtain the full-cycle settlement data of the protected object, and invert and calculate the allowable displacement control threshold required to maintain the protected object.

[0037] It should be noted that the cemented backfill stope engineering parameter design system of the present invention can also perform any of the processes described in the previously described cemented backfill stope engineering parameter design method, the specific details of which will not be repeated here.

[0038] Specific Cases The implementation of this invention is illustrated through a backfilling project in a coal mine in Shanxi Province. The steps are as follows: Step 1: Establish a database and determine input parameters through multi-factor coupling tests. Conduct mineralization and mechanical property tests on the backfill material to construct a database containing the theoretical carbon dioxide sequestration potential and mineralization and mechanical properties of the backfill material, including "mineralization degree-time-strength". Detailed mineralization characteristic tests were performed on the proposed fly ash and coal gangue mixed backfill material, revealing a calcium oxide content of 12.5% ​​and a magnesium oxide content of 2.1%. Based on the above test data, the theoretical carbon dioxide sequestration potential of the material was calculated using the modified Steinour formula and an engineering correction factor β of 0.8. The material density is 0.12 tons of CO2 / ton, combined with the wet density of the filling material (ρ=1850kg / m³). 3 Based on the water content (ω=28%), the carbon sequestration per unit volume of the infill material was calculated. Approximately 138 kg / m 3 This established the upper limit of the carbon sequestration potential of this project in terms of materials. Simultaneously, experiments showed that when CO2 was introduced to reach saturated mineralization (α=0.8), the elastic modulus of the filling material was affected by the depletion of active calcium and interfacial damage effects. The unmineralized baseline of 2.0 GPa was reduced to 1.2 GPa; the measured data were entered into the database as core material parameters and provided as a reference for subsequent steps.

[0039] Step 2: Numerical Simulation Modeling and Determination of Critical Support Parameters. Based on step S20 of this invention, a numerical simulation model and mechanical constraints for the movement of surrounding rock in the mining area are constructed. Combining mine geological data, the protected object is identified as the aquifer located 60m above the coal seam roof above the mining area, with the main key layer determined to be 18m thick fine sandstone. Based on the database established in S10, a numerical simulation model considering mineralization damage and spatial layout is constructed. Mechanical degradation parameters under different mineralization degrees are mapped into the model, and corresponding spatial distribution models of the filling body and roadway are established to simulate the characteristics of surrounding rock movement. Based on the deformation resistance of the protected object (the aquifer in this example), the allowable displacement control threshold at the protected object is determined through numerical simulation inversion to ensure that no lifting fractures occur at the bottom of the aquifer. The value is 200mm. Based on the principle of equivalent stiffness of elastic foundation, a criterion for the critical deformation resistance required for the stope support system is constructed. The equivalent load strength parameters of the rock mass above the goaf in the vertical direction are known. The pressure is 11.25 MPa, and the influence range parameter Γ of the goaf in the horizontal direction is 5000 m. 2 (Calculated based on a single pressing step distance). Substituting the above parameters into the critical deformation resistance criterion, the critical equivalent deformation resistance parameters that the stope support system must provide are calculated. At least 2.81 × 10 5 MN / m. This value is set as the hard baseline for the constraint function G(X) in the subsequent optimization model.

[0040] Step 3: Construction of a multi-objective optimization mathematical model. Based on the method described in this invention, a multi-objective collaborative optimization model is constructed and solved.

[0041] Decision variables and target setting: The layout pattern of the filled roadway (quantified as the filling layout coefficient λ), the cementitious agent content, and the CO2 gas-liquid ratio were selected as decision variables. Under the premise of ensuring the safety of the protected object, the total carbon sequestration J was used as the target. C Maximize, overall cost J E Minimize the objective function.

[0042] Constraint function construction and calculation: Construct the constraint function G(X), where the system's equivalent resistance to deformation is... Calculated by the formula, The database information established by S10 is invoked. The model execution results show that, under these conditions, if the traditional spaced strip filling (λ=0.5) is used, the calculated equivalent deformation resistance of the system is... Much smaller than the critical threshold There is a great risk of water inrush; if it is adjusted to fill all lanes one by one (λ=1.0), that is, by increasing the filling volume to compensate for the loss of material strength, the calculated equivalent deformation resistance of the system is significantly improved and exceeds the critical threshold, and the predicted roof subsidence is only 150mm, which can meet the safety requirements.

[0043] Step 4, Model Solving and Engineering Implementation Feedback Adjustment: Based on the method described in step S40 of this invention, perform optimization calculations and closed-loop corrections.

[0044] Solution and Engineering Implementation: such as Figure 2 As shown, the algorithm is used to optimize the model and output the Pareto front solution set. Taking into account economic and environmental indicators, an optimal parameter set of "high filling rate (λ=1) + medium binder content + high mineralization" was selected for field implementation.

[0045] Feedback and adjustment optimization: such as Figure 3 As shown, monitoring data during implementation revealed a maximum subsidence of 155mm in the underground roof, a deviation of only 3.3% compared to the model prediction of 150mm, validating the effectiveness of the coal pillar-free full-filling strategy. An error feedback correction model was constructed, and the equivalent correction coefficient ξ in the model was inverted and calibrated, completing the closed-loop iteration of the design and providing a more accurate parameter benchmark for the next stage of engineering design.

[0046] This embodiment verifies that, in addressing the problem of weakened mineralization intensity, the method proposed in this invention saves approximately 25% of material costs and increases carbon sequestration capacity by 100% compared to the traditional method of simply increasing cement usage, achieving an effective synergy of safety, economy, and environmental protection.

[0047] The foregoing description, with reference to preferred embodiments, details an exemplary implementation of the cemented backfill mining area engineering parameter design method and system proposed by the present invention. However, those skilled in the art will understand that various modifications and alterations can be made to the above specific embodiments without departing from the concept of the present invention, and various combinations can be made to the various technical features and structures proposed by the present invention without exceeding the protection scope of the present invention, which is determined by the appended claims.

Claims

1. A method for designing engineering parameters for cemented backfilling stopes, characterized in that, Includes the following steps: S10: Establish a database of theoretical carbon dioxide sequestration potential and mineralization mechanical properties of cemented backfill materials through multi-factor coupled laboratory testing of CO2 mineralization of cemented backfill materials; S20: Based on the above database analysis of the mining geological conditions and backfilling requirements of the mine, and based on the properties of the surrounding rock and the backfilling technology of the stope, the maximum allowable deformation of the protected object is inverted through a numerical simulation model; the critical support stiffness of the stope support system is determined by combining the maximum allowable deformation with the principle of equivalent stiffness of elastic foundation. S30: Using the layout pattern and material ratio of the filling tunnel as decision variables, and under the premise of ensuring the safety of the protected object, a collaborative optimization model is established with the total carbon sequestration and comprehensive economic cost as optimization objectives, and the Pareto optimal engineering parameter set is solved by optimization algorithm; S40: Apply the optimal parameters to the field, and adjust the layout mode of the filling tunnel and the material ratio parameters according to the feedback from field practice to obtain the optimal solution under the requirements.

2. The method for designing engineering parameters for cemented backfilling stopes according to claim 1, characterized in that, In step S10, the theoretical carbon dioxide sequestration potential of the filling material is determined. The calculation is performed using the modified Steinour formula, which is expressed as follows: In the formula, , , , and Each chemical formula represents the mass percentage of the corresponding oxide in the material; β is the engineering correction factor.

3. The method for designing engineering parameters for cemented backfilling stopes according to claim 1, characterized in that, In step S20, based on the properties of the surrounding rock and the backfilling process of the stope, the maximum allowable deformation of the protected object is inverted through a numerical simulation model, specifically including the following steps: S21: Based on the database of mineralization mechanical property evolution, establish a constitutive equation that reflects the evolution of the strength of the filling body with the degree of mineralization, and map the mechanical parameters under different mineralization degrees to the model unit; S22: Based on the mining geological conditions and typical backfill roadway layout patterns, establish a corresponding spatial distribution model of backfill bodies and roadway retention. S23: Simulate the movement characteristics of the surrounding rock in the mining area under the combined effect of the strength evolution of the backfill and the spatial layout through numerical simulation model, obtain the full-cycle settlement data of the protected object, and use this to invert and calculate the allowable displacement control threshold required to maintain the protected object.

4. The method for designing engineering parameters for cemented backfilling stopes according to claim 1, characterized in that, Step S20 further includes: based on the principle of equivalent stiffness of elastic foundation, and according to the deformation control requirements of the protected object, constructing a criterion for the critical deformation resistance capacity required by the mining support system, which satisfies the following relationship: In the formula, The critical equivalent deformation resistance parameter required for the mining support system under exposed goaf conditions; The equivalent load strength parameter of the rock mass above the goaf acting vertically on the mining area; This refers to the parameter representing the extent of the influence of the goaf in the horizontal direction. The allowable displacement control threshold is determined based on the safety status of the protected object.

5. The method for designing engineering parameters for cemented backfilling stopes according to claim 1, characterized in that, In step S30, a collaborative optimization model is established with the total carbon sequestration and comprehensive economic cost as the optimization objectives. This specifically includes the following steps: S31: Design variable X n The layout pattern of the filling roadway, the cementitious agent ratio, and the CO2 content are selected as decision variables; wherein, the layout pattern of the filling roadway is quantitatively characterized by the filling layout coefficient λ. S32: Constructing the objective function F(X): including: constructing the function to maximize total carbon sequestration J C and minimizing the overall cost J E ; Among them, maximizing the total carbon sequestration J C The expression is: In the formula, Let λ be the total volume of the goaf in the mining area, and λ be the filling layout coefficient. Carbon sequestration per unit volume of filling material; Among them, minimizing the comprehensive cost J E The expression is: In the formula, For material costs, For process costs; S33: Construct the constraint function G(X); its expression is: In the formula, These are the critical deformation resistance parameters for the mining support system. In design variable X n The equivalent deformation resistance function of the mining support system under certain conditions.

6. The method for designing engineering parameters for cemented backfilling stopes according to claim 5, characterized in that, In step S32, the amount of carbon fixed per unit volume of filling material The expression is: In the formula, Theoretical carbon dioxide sequestration potential, Mineralization The wet density of the filling material; This represents the water content of the filling material.

7. The method for designing engineering parameters for cemented backfilling stopes according to claim 5, characterized in that, In step S32, the equivalent deformation resistance function of the mining support system is... The expression is: In the formula, An equivalent correction coefficient reflecting the stress state and structural synergy effect of the mining support system. The elastic modulus of the infill material whose strength has decreased after carbon dioxide mineralization. The characteristic height parameter is used to characterize the spatial scale of the mining area.

8. The method for designing engineering parameters for cemented backfilling stopes according to claim 1, characterized in that, In step S40, based on feedback from field practice, the layout pattern of the filling tunnel and the material ratio parameters are adjusted to obtain the optimal solution under the requirements. The specific steps are as follows: S41: Solution stage: The mathematical model is optimized using a multi-objective optimization algorithm, and the Pareto front solution set that satisfies the constraints is output. S42: Feedback and Correction Phase: Select the target solution from the Pareto front for engineering applications and monitor the actual deformation evolution data of the mining area; Calculate the deviation rate between the measured data and the theoretical prediction, construct the error feedback correction equation, and use the model to apply the equivalent correction coefficients within the constraint function in step S30. Perform inversion calibration, and use the calibrated parameters to perform a new round of optimization solutions until the target requirements of the protected object are met.

9. A system for designing engineering parameters for cemented backfilling stopes, characterized in that, include: The database module is configured to establish a database of the theoretical carbon dioxide sequestration potential and mineralization mechanical properties of cemented backfill materials through multi-factor coupled laboratory testing of CO2 mineralization of cemented backfill materials. The inversion and support stiffness module is configured to analyze the mining geological conditions and backfilling requirements of the mine based on the above database, and invert the maximum allowable deformation of the protected object through a numerical simulation model based on the surrounding rock properties and the backfilling process of the stope; and determine the critical support stiffness of the stope support system by combining the maximum allowable deformation with the principle of equivalent stiffness of elastic foundation. The collaborative optimization module is configured to use the layout mode and material ratio of the filling tunnel as decision variables, and to establish a collaborative optimization model with the total carbon sequestration and comprehensive economic cost as optimization objectives under the premise of ensuring the safety of the protected object. The Pareto optimal engineering parameter set is then solved through the optimization algorithm. The feedback and adjustment module is configured to apply the optimal parameters to the field and adjust the filling tunnel layout and material ratio parameters based on field feedback to obtain the optimal solution under the requirements.

10. The cemented backfilling stope engineering parameter design system according to claim 9, characterized in that, The inversion and support stiffness module includes: The constitutive model unit is configured to establish a constitutive equation reflecting the evolution of the strength of the filling body with the degree of mineralization based on the database of mineralization mechanical property evolution, and to map the mechanical parameters under different mineralization degrees to the model unit; The spatial distribution model unit is configured to establish a corresponding spatial distribution model of the filling body and the roadway based on the mining geological conditions and typical filling roadway layout patterns of the mine. The displacement inversion calculation unit is configured to simulate the movement characteristics of the surrounding rock in the mining area under the combined effect of the strength evolution of the backfill and the spatial layout through a numerical simulation model, obtain the full-cycle settlement data of the protected object, and invert and calculate the allowable displacement control threshold required to maintain the protected object.

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